I've been struggling with 5.1 digital PCM audio playback for many years. . . Finally got it to work in R6.03 with analog settings.
PCM for Recordings playback settings: (to be edited)
Service Menu
MythTv Configuration --> Setup --> General --> Audio System
Audio output device: /dev/dps0
Speaker configuration: 5.1
Upconvert stereo to 5.1 surround <check>
Upmix: Fastest
Digital output device: Default
Dolby Digital <checked> DTS <checked>
Service Menu
LinHES Configuration --> Audio Settings -->
Sound card driver: OSS
Type: Analog
Nvidia MCP51(dsp0)
xine <checked> mplayer <checked> mythmusic <checked> mythfrontend <checked>
Here is the OSS info output:
Code:
[root@MythTVboxen mythtv]# ossinfo
Version info: OSS 4.1 (b 1051/200902180218) (0x00040100) GPL
Platform: Linux/i686 2.6.28-LinHES #1 SMP PREEMPT Sun Nov 1 06:47:02 UTC 2009 (MythTVboxen)
Number of audio devices: 2
Number of audio engines: 7
Number of mixer devices: 1
Device objects
0: osscore0 OSS core services
1: oss_ich0 Nvidia MCP51 interrupts=934962 (1214967)
2: oss_usb0 USB audio core services
Mixer devices
0: ICH AC97 Mixer (ALC850) (Mixer 0 of device object 1)
Audio devices
Nvidia MCP51 /dev/oss/oss_ich0/pcm0 (device index 0)
Nvidia MCP51 S/PDIF out /dev/oss/oss_ich0/spdout (device index 1)
OSSMIX output:
Code:
[root@MythTVboxen mythtv]# ossmix | grep -i vmix
vmix0-enable ON|OFF (currently ON)
vmix0-rate <decimal value> (currently 48000) (Read-only)
vmix0-channels <Stereo|Multich> (currently Stereo)
vmix0-src <Fast|Low|Medium|High|High+|Production|OFF> (currently Fast)
vmix0-outvol <monovol> (currently 25.0 dB)
vmix0-invol <monovol> (currently 25.0 dB)
vmix0.pcm1 [<leftvol>:<rightvol>] (currently 25.0:25.0 dB) ("mplayer")
vmix0.pcm2 [<leftvol>:<rightvol>] (currently 25.0:25.0 dB)
vmix0.pcm3 [<leftvol>:<rightvol>] (currently 25.0:25.0 dB)
vmix0.pcm4 [<leftvol>:<rightvol>] (currently 25.0:25.0 dB)
Still having issues with mplayer playback
added -afm hwac3 to the default player to try and get 5.1 playback but ended up not being able to play and this error in mythfrontend.log.
Code:
Playing /myth/video/RATATOUILLE.m4v.
libavformat file format detected.
[lavf] Video stream found, -vid 0
[lavf] Audio stream found, -aid 1
[lavf] Subtitle stream found, -sid 0
VIDEO: [avc1] 720x360 24bpp 23.976 fps 0.0 kbps ( 0.0 kbyte/s)
Xlib: extension "Generic Event Extension" missing on display ":0.0".
Xlib: extension "Generic Event Extension" missing on display ":0.0".
Xlib: extension "Generic Event Extension" missing on display ":0.0".
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264)
==========================================================================
==========================================================================
Trying to force audio codec driver family hwac3...
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to AC3, 448000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, ac3, 448.0 kbit/29.17% (ratio: 56000->192000)
Selected audio codec: [hwac3] afm: hwac3 (AC3 through S/PDIF)
==========================================================================
[AO OSS] Can't set audio device /dev/dsp to ac3 output, trying s16le...
AO: [oss] 48000Hz 2ch s16le (2 bytes per sample)
[format] Sample format big-endian AC3 not yet supported
[libaf] Reinitialization did not work, audio filter 'format' returned error code -2
Couldn't find matching filter/ao format!
Starting playback...
MPlayer interrupted by signal 11 in module: decode_audio
- MPlayer crashed by bad usage of CPU/FPU/RAM.
Recompile MPlayer with --enable-debug and make a 'gdb' backtrace and
disassembly. Details in DOCS/HTML/en/bugreports_what.html#bugreports_crash.
- MPlayer crashed. This shouldn't happen.
It can be a bug in the MPlayer code _or_ in your drivers _or_ in your
gcc version. If you think it's MPlayer's fault, please read
DOCS/HTML/en/bugreports.html and follow the instructions there. We can't and
won't help unless you provide this information when reporting a possible bug.